In what would be one of the strangest Hollywood showdowns in history, Bieber, 25, challenged the 56-year-old actor to a bout, boldly claiming the ‘Mission: Impossible’ star would “never live it down” if he denied the match.

Never one to miss out on a PR opportunity, former UFC two-weight champion Conor McGregor chimed in to offer to host the fight if “Tom Cruise is man enough to accept.”

If Tom Cruise is man enough to accept this challenge,McGregor Sports and Entertainment will host the bout.Does Cruise have the sprouts to fight, like he does in the movies? Stay tuned to find out! https://t.co/TxsH9KUyFg

In what could soon turn out to be the most high-profile celebrity tournaments of all time, McGregor then posed his own challenge to actor Mark Walhberg to fight on the same card.

I challenge Mark Walhberg on the very same card.Back when mark wahlberg was marky mark, I’d’ve still slapped the ears off him and took my ufc shares back.#Shares#Streams#Dazn#EspnMcGregor Sports and Entertainment